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<a href="null_8c.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="comment">  FUSE: Filesystem in Userspace</span></div><div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment">  Copyright (C) 2001-2007  Miklos Szeredi &lt;miklos@szeredi.hu&gt;</span></div><div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment"></span></div><div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="comment">  This program can be distributed under the terms of the GNU GPL.</span></div><div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="comment">  See the file COPYING.</span></div><div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="comment">*/</span></div><div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;</div><div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;<span class="preprocessor">#define FUSE_USE_VERSION 31</span></div><div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;</div><div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;<span class="preprocessor">#include &lt;<a class="code" href="fuse_8h.html">fuse.h</a>&gt;</span></div><div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;<span class="preprocessor">#include &lt;<a class="code" href="fuse__lowlevel_8h.html">fuse_lowlevel.h</a>&gt;</span></div><div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;<span class="preprocessor">#include &lt;stdio.h&gt;</span></div><div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="preprocessor">#include &lt;stdlib.h&gt;</span></div><div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="preprocessor">#include &lt;string.h&gt;</span></div><div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;<span class="preprocessor">#include &lt;unistd.h&gt;</span></div><div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;<span class="preprocessor">#include &lt;time.h&gt;</span></div><div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="preprocessor">#include &lt;errno.h&gt;</span></div><div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;</div><div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> null_getattr(<span class="keyword">const</span> <span class="keywordtype">char</span> *path, <span class="keyword">struct</span> stat *stbuf,</div><div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;                        <span class="keyword">struct</span> <a class="code" href="structfuse__file__info.html">fuse_file_info</a> *fi)</div><div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;{</div><div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;        (void) fi;</div><div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;</div><div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;        <span class="keywordflow">if</span>(strcmp(path, <span class="stringliteral">&quot;/&quot;</span>) != 0)</div><div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;                <span class="keywordflow">return</span> -ENOENT;</div><div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;</div><div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;        stbuf-&gt;st_mode = S_IFREG | 0644;</div><div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;        stbuf-&gt;st_nlink = 1;</div><div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;        stbuf-&gt;st_uid = getuid();</div><div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;        stbuf-&gt;st_gid = getgid();</div><div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;        stbuf-&gt;st_size = (1ULL &lt;&lt; 32); <span class="comment">/* 4G */</span></div><div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;        stbuf-&gt;st_blocks = 0;</div><div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;        stbuf-&gt;st_atime = stbuf-&gt;st_mtime = stbuf-&gt;st_ctime = time(NULL);</div><div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;</div><div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;        <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;}</div><div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;</div><div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> null_truncate(<span class="keyword">const</span> <span class="keywordtype">char</span> *path, off_t size,</div><div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;                         <span class="keyword">struct</span> <a class="code" href="structfuse__file__info.html">fuse_file_info</a> *fi)</div><div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;{</div><div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;        (void) size;</div><div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;        (void) fi;</div><div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;</div><div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;        <span class="keywordflow">if</span>(strcmp(path, <span class="stringliteral">&quot;/&quot;</span>) != 0)</div><div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;                <span class="keywordflow">return</span> -ENOENT;</div><div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;</div><div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;        <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;}</div><div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;</div><div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> null_open(<span class="keyword">const</span> <span class="keywordtype">char</span> *path, <span class="keyword">struct</span> <a class="code" href="structfuse__file__info.html">fuse_file_info</a> *fi)</div><div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;{</div><div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;        (void) fi;</div><div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;</div><div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;        <span class="keywordflow">if</span>(strcmp(path, <span class="stringliteral">&quot;/&quot;</span>) != 0)</div><div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;                <span class="keywordflow">return</span> -ENOENT;</div><div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;</div><div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;        <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;}</div><div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;</div><div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> null_read(<span class="keyword">const</span> <span class="keywordtype">char</span> *path, <span class="keywordtype">char</span> *buf, <span class="keywordtype">size_t</span> size,</div><div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;                     off_t offset, <span class="keyword">struct</span> <a class="code" href="structfuse__file__info.html">fuse_file_info</a> *fi)</div><div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;{</div><div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;        (void) buf;</div><div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;        (void) offset;</div><div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;        (void) fi;</div><div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;</div><div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;        <span class="keywordflow">if</span>(strcmp(path, <span class="stringliteral">&quot;/&quot;</span>) != 0)</div><div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;                <span class="keywordflow">return</span> -ENOENT;</div><div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;</div><div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;        <span class="keywordflow">if</span> (offset &gt;= (1ULL &lt;&lt; 32))</div><div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;                <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;</div><div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;        memset(buf, 0, size);</div><div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;        <span class="keywordflow">return</span> size;</div><div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;}</div><div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160;</div><div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> null_write(<span class="keyword">const</span> <span class="keywordtype">char</span> *path, <span class="keyword">const</span> <span class="keywordtype">char</span> *buf, <span class="keywordtype">size_t</span> size,</div><div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;                      off_t offset, <span class="keyword">struct</span> <a class="code" href="structfuse__file__info.html">fuse_file_info</a> *fi)</div><div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;{</div><div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;        (void) buf;</div><div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;        (void) offset;</div><div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;        (void) fi;</div><div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;</div><div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;        <span class="keywordflow">if</span>(strcmp(path, <span class="stringliteral">&quot;/&quot;</span>) != 0)</div><div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;                <span class="keywordflow">return</span> -ENOENT;</div><div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;</div><div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;        <span class="keywordflow">return</span> size;</div><div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;}</div><div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;</div><div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;<span class="keyword">static</span> <span class="keyword">struct </span><a class="code" href="structfuse__operations.html">fuse_operations</a> null_oper = {</div><div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;        .<a class="code" href="structfuse__operations.html#ac39a0b7125a0e5001eb5ff42e05faa5d">getattr</a>        = null_getattr,</div><div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;        .truncate       = null_truncate,</div><div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;        .open           = null_open,</div><div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;        .read           = null_read,</div><div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;        .write          = null_write,</div><div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;};</div><div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;</div><div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;<span class="keywordtype">int</span> main(<span class="keywordtype">int</span> argc, <span class="keywordtype">char</span> *argv[])</div><div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;{</div><div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160;        <span class="keyword">struct </span><a class="code" href="structfuse__args.html">fuse_args</a> args = <a class="code" href="fuse__opt_8h.html#a9bea40fe56b18be9aa110185ab7387ed">FUSE_ARGS_INIT</a>(argc, argv);</div><div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160;        <span class="keyword">struct </span>fuse_cmdline_opts opts;</div><div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;        <span class="keyword">struct </span>stat stbuf;</div><div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;</div><div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160;        <span class="keywordflow">if</span> (<a class="code" href="fuse__lowlevel_8h.html#a8421a0cb3b6fb7013c7272c6997d1e08">fuse_parse_cmdline</a>(&amp;args, &amp;opts) != 0)</div><div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;                <span class="keywordflow">return</span> 1;</div><div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;        <a class="code" href="fuse__opt_8h.html#a2cdf272429ab3869a5162976141b287d">fuse_opt_free_args</a>(&amp;args);</div><div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;</div><div class="line"><a name="l00125"></a><span class="lineno">  125</span>&#160;        <span class="keywordflow">if</span> (!opts.mountpoint) {</div><div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160;                fprintf(stderr, <span class="stringliteral">&quot;missing mountpoint parameter\n&quot;</span>);</div><div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;                <span class="keywordflow">return</span> 1;</div><div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160;        }</div><div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;</div><div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160;        <span class="keywordflow">if</span> (stat(opts.mountpoint, &amp;stbuf) == -1) {</div><div class="line"><a name="l00131"></a><span class="lineno">  131</span>&#160;                fprintf(stderr ,<span class="stringliteral">&quot;failed to access mountpoint %s: %s\n&quot;</span>,</div><div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;                        opts.mountpoint, strerror(errno));</div><div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;                free(opts.mountpoint);</div><div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160;                <span class="keywordflow">return</span> 1;</div><div class="line"><a name="l00135"></a><span class="lineno">  135</span>&#160;        }</div><div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;        free(opts.mountpoint);</div><div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;        <span class="keywordflow">if</span> (!S_ISREG(stbuf.st_mode)) {</div><div class="line"><a name="l00138"></a><span class="lineno">  138</span>&#160;                fprintf(stderr, <span class="stringliteral">&quot;mountpoint is not a regular file\n&quot;</span>);</div><div class="line"><a name="l00139"></a><span class="lineno">  139</span>&#160;                <span class="keywordflow">return</span> 1;</div><div class="line"><a name="l00140"></a><span class="lineno">  140</span>&#160;        }</div><div class="line"><a name="l00141"></a><span class="lineno">  141</span>&#160;</div><div class="line"><a name="l00142"></a><span class="lineno">  142</span>&#160;        <span class="keywordflow">return</span> <a class="code" href="fuse_8h.html#ac99b844cee7aaa8fb4e35df5b5488d82">fuse_main</a>(argc, argv, &amp;null_oper, NULL);</div><div class="line"><a name="l00143"></a><span class="lineno">  143</span>&#160;}</div><div class="ttc" id="fuse__lowlevel_8h_html_a8421a0cb3b6fb7013c7272c6997d1e08"><div class="ttname"><a href="fuse__lowlevel_8h.html#a8421a0cb3b6fb7013c7272c6997d1e08">fuse_parse_cmdline</a></div><div class="ttdeci">int fuse_parse_cmdline(struct fuse_args *args, struct fuse_cmdline_opts *opts)</div><div class="ttdef"><b>Definition:</b> <a href="helper_8c_source.html#l00202">helper.c:202</a></div></div>
<div class="ttc" id="structfuse__file__info_html"><div class="ttname"><a href="structfuse__file__info.html">fuse_file_info</a></div><div class="ttdef"><b>Definition:</b> <a href="fuse__common_8h_source.html#l00037">fuse_common.h:37</a></div></div>
<div class="ttc" id="structfuse__operations_html"><div class="ttname"><a href="structfuse__operations.html">fuse_operations</a></div><div class="ttdef"><b>Definition:</b> <a href="fuse_8h_source.html#l00299">fuse.h:299</a></div></div>
<div class="ttc" id="fuse__opt_8h_html_a2cdf272429ab3869a5162976141b287d"><div class="ttname"><a href="fuse__opt_8h.html#a2cdf272429ab3869a5162976141b287d">fuse_opt_free_args</a></div><div class="ttdeci">void fuse_opt_free_args(struct fuse_args *args)</div><div class="ttdef"><b>Definition:</b> <a href="fuse__opt_8c_source.html#l00033">fuse_opt.c:33</a></div></div>
<div class="ttc" id="structfuse__operations_html_ac39a0b7125a0e5001eb5ff42e05faa5d"><div class="ttname"><a href="structfuse__operations.html#ac39a0b7125a0e5001eb5ff42e05faa5d">fuse_operations::getattr</a></div><div class="ttdeci">int(* getattr)(const char *, struct stat *, struct fuse_file_info *fi)</div><div class="ttdef"><b>Definition:</b> <a href="fuse_8h_source.html#l00311">fuse.h:311</a></div></div>
<div class="ttc" id="fuse_8h_html"><div class="ttname"><a href="fuse_8h.html">fuse.h</a></div></div>
<div class="ttc" id="fuse__lowlevel_8h_html"><div class="ttname"><a href="fuse__lowlevel_8h.html">fuse_lowlevel.h</a></div></div>
<div class="ttc" id="structfuse__args_html"><div class="ttname"><a href="structfuse__args.html">fuse_args</a></div><div class="ttdef"><b>Definition:</b> <a href="fuse__opt_8h_source.html#l00109">fuse_opt.h:109</a></div></div>
<div class="ttc" id="fuse__opt_8h_html_a9bea40fe56b18be9aa110185ab7387ed"><div class="ttname"><a href="fuse__opt_8h.html#a9bea40fe56b18be9aa110185ab7387ed">FUSE_ARGS_INIT</a></div><div class="ttdeci">#define FUSE_ARGS_INIT(argc, argv)</div><div class="ttdef"><b>Definition:</b> <a href="fuse__opt_8h_source.html#l00123">fuse_opt.h:123</a></div></div>
<div class="ttc" id="fuse_8h_html_ac99b844cee7aaa8fb4e35df5b5488d82"><div class="ttname"><a href="fuse_8h.html#ac99b844cee7aaa8fb4e35df5b5488d82">fuse_main</a></div><div class="ttdeci">#define fuse_main(argc, argv, op, private_data)</div><div class="ttdef"><b>Definition:</b> <a href="fuse_8h_source.html#l00855">fuse.h:855</a></div></div>
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